Vibrato systems for guitars are well known as shown, for example, in U.S. Pat. No. 4,171,661. These systems are generally sold as an attachment to existing guitars and can be operated by way of an actuating lever to simultaneously relax the tension of all the strings of the guitar to a small degree, thereby detuning it slightly.
Existing vibrato systems have the disadvantage of being difficult to adjust for various string spacings, and producing a harsher sound than desirable. Furthermore, a number of guitarists consider it desirable to have the opportunity of leaving the actuating lever in a forward position between uses, or to have it swing out of the way under its own weight whenever it is not in use.